They may be admissible- depending on things such as content and purpose for admission. Florida is a "no fault" divorce state. Whether your spouse was involved in an elicit relationship may or may not be relevant. The court does not generally care about the bad behavior of either party in granting a dissolution of marriage, but it could be an issue; for example, if you are claiming that your spouse dissipated marital assets by spending on an extramarital affair. You should speak to an attorney for further information.
Legal disclaimer: this response is not intended to create any attorney-client relationship and is based on the limited facts given and should not be relied on as legal advice. It is recommended that you consult with an attorney before taking any action based on the foregoing statements.
Admission of evidence is controlled by the Rules of Evidence. These are suprisingly complex. You would need an attorney to navigate that maze. In the end, the court may just yawn. If you are getting a divorce, just get one. The court will not stand up at the end and chastise her. Find a family law attorney, file for divorce, and move on. First you heal, then you seek healthy relationships.
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